Access to the Apple Store is blocked this morning, it is indeed a pre-order day (from 2 p.m.). More particularly for AirTags that can be purchased individually for € 35 or per pack from € 4 to € 119 (reminder: up to 16 tags can be associated with an Apple ID).
The other novelty in pre-order today is the color purple for the iPhone 12 and 12 mini. These products will be delivered to customers on April 30 and it is on this same date that we can order the rest (iMac, iPad Pro, Apple TV, Siri Remote, etc.).